As one of the most attractive but challenging synthetic approaches to enrich the methodology of MOF chemistry, “one-pot” in situ synthetic approach has been attracted more and more attention due to its circumvention of the organic ligands synthesis process. Herein, we present a Zn(II)-based metal-organic framework (MOF) formulated as {[Zn(pcd)]}_n (1) generated from the “one-pot” in situ reaction, where isonicotinic acid N'-(pyridine-4-carbonyl)-hydrazide (pcd) is formed by the hydrolysis reaction of the bent 2,5-bis(4-pyridyl)-1,3,4-oxadiazole (bpo) ligand. 1 demonstrates a 3D 4, 4-connected cds topological structure based on Zn₂N₂ secondary building unit (SUB). The variation of luminescence emission towards CrO₄²⁻/Cr₂O₇²⁻ anions shows that 1 is a promisingly selective, sensitive and recyclable fluorescence turn-off sensor in the quantitative recognition of CrO₄²⁻/Cr₂O₇²⁻ anions. And the detection limit can reach as low as 5.25 μM for CrO₄²⁻ anions and 7.64 μM for Cr₂O₇²⁻ anions. Moreover, the mechanism of fluorescence behavior of 1 towards CrO₄²⁻/Cr₂O₇²⁻ anions is interpreted with the UV–Vis spectral overlap experiments.

作为丰富MOF化学方法学中最具吸引力但最具挑战性的合成方法之一，“一锅法”原位合成方法由于其规避有机配体合成过程而受到越来越多的关注。在此，我们提出了一种通过“一锅法”原位反应生成的Zn(II) 基金属有机骨架 (MOF)，其配方为 {[Zn(pcd)]} n ( ₁ )，其中异烟酸 N'- (吡啶-4-羰基)-酰肼(pcd)是通过弯曲的2,5-双(4-吡啶基)-1,3,4-恶二唑(bpo)配体的水解反应形成的。图1展示了基于Zn ₂ N ₂的3D 4, 4连接的cds拓扑结构次要建筑单元（SUB）。_{CrO 4} ²⁻ /Cr ₂ O ₇ ²⁻阴离子的发光发射变化表明，1是一种在 CrO ₄ ²⁻ /Cr ₂ O ₇ ²⁻定量识别中很有前景的选择性、灵敏且可回收的荧光关闭传感器。阴离子。_{CrO 4} ²⁻阴离子的检测限可低至 5.25 μM ，Cr ₂ O ₇ ²⁻阴离子的检测限可低至 7.64 μM。此外， 1对CrO ₄ ²⁻ /Cr ₂的荧光行为机制O ₇ ²⁻阴离子通过紫外-可见光谱重叠实验进行解释。